Power operated tyepwriter with means for error correction

ABSTRACT

A power operated typewriter having a special key for operating a special type font for effecting correction of errors. The type bar carrying the type font is structurally modified so that when actuated it will not cause advancement of the carriage. A special link connects the type bar actuating mechanism with the feed arm of the ribbon vibrator mechanism. Actuation of the key will not result in movement of the carriage but will result in elevation of the lower ribbon portion carrying obliterating pigment into registration with the type font so that pigment is deposited over a character imprinted in error.

waited States Patent Ozimek et a1.

POWER OPERATED TYEPWRITER WITH MEANS FOR ERROR CORRECTION Inventors:Chester E. Ozimek, Park Ridge;

Kenneth L. Eldridge, .lr., Naperville. both, 111.

Assignee: Sears, Roebuck and Co., Chicago.

Filed: Sept. 18, 1973 Appl. No.: 398,532

US. Cl 197/181, 197/83, 197/157 lnt. Cl B4lj 29/36 Field of Search197/91, 154, 157, 181

References Cited UNITED STATES PATENTS Scheinpflug 197/157 Ozimek et a1197/181 X Rava et a1 197/181 X Jan. 28, 1975 Primary Examiner-Edgar S.Burr Assistant Examiner-Paul T. Sewell Attorney, Agent, orFirm-Arnstein, Gluck. Weitzenfeld & Minow 57; ABSTRACT A power operatedtypewriter having a special key for operating a special type font foreffecting correction of errors. The type bar carrying the type font isstructurally modified so that when actuated it will not causeadvancement of the carriage. A special link com nects the type baractuating mechanism with the feed arm of the ribbon vibrator mechanism.Actuation of the key will not result in movement of the carriage butwill result in elevation of the lower ribbon portion carryingobliterating pigment into registration with the type font so thatpigment is deposited over a character imprinted in error.

1 Claim, 6 Drawing Figures TED JRH28I975 PATE sum HP 2 POWER OPERATEDTYEPWRITER WITH MEANS FOR ERROR CORRECTION BACKGROUND OF THE INVENTIONThe present invention relates to a power operated typewriter embodyingerror correction features adapted for use with a composite doublestriped ribbon, one longitudinal half of which is inked to makecharacter impressions on paper in the usual manner and the other half ofwhich carries a pressure transferable opaque adherent pigment which whenapplied over the error renders it substantially invisible so that acorrect character may be imprinted thereon.

SUMMARY OF THE INVENTION The power operated typewriter of the presentinvention embodies a special key linked to a type bar carrying auniversal obliterating type font and having a unique cut-out arranged toclear the escapement bail so as not to actuate the escapement system andeffect stepwise movement of the carriage. vThe type bar is connected bylinkage to the feed arm of the ribbon vibrator. When the key isactuated, the movement of the type bar effects maximum movement of thefeed arm causing the ribbon to move to its uppermost position to alignthe pigment carrying portion of the ribbon with the type font. Thereturn of the special key to at rest position restores the printing andescapement systems to normal operating conditions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective exploded viewshowing the cooperative relationship of the various parts of theinvention in a power operated typewriter.

FIG. 2 is a fragmentary rear perspective view, on an enlarged scale, ofa type bar carrying a universal obliterating type font.

FIGS. 3 through 6 are side elevational views of the feed arm componentof the ribbon vibrator mechanism in various positions of operation.

BRIEF DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawings,the invention is shown as applied to a well known make of commercialpower operated typewriter and only those parts of the apparatus whichcontribute directly to the essentials of the present invention have beenincluded in the drawing. The typewriter, not shown, generally isprovided with the usual bank of keys manually actuable for initiatingthe imprinting of characters, a space bar, key controlled power meansincluding a universal driving element or toothed rotary snatch roll, aplaten roller and carriage, conventional carriage spacing mechanism, abackspace key for producing letter width stepwise movements of thecarriage in a rearward direction, a ribbon field control selector andribbon carrying spools for the ribbon.

Our invention includes the provision of a special key 10 and type font11, the key being preferably located on the right hand side of the bankof keys and operatively connected to mechanism performing particularfunctions. hereinafter to be described.

Referring to FIG. I, the typewriter is provided with the usual vibrator12 carrying a special ribbon 13, the upper longitudinal one half ofwhich comprises a inking portion 13a while the lower longitudinal onehalf 13b carries a pressure transferable opaque adherent pigment. Thevibrator 12 is reciprocally actuated in a vertical direction by an arm14 fixed on a rock shaft 16 to one end to which is rigidly connected afeed arm 17 of the ribbon vibrator mechanism. The feed arm 17 of thepresent invention is structurally modified and differs from theconventional feed arm in that it has a cutaway or clearance portion l8and is provided with a laterally extending pierced lug 19. It will benoted that in a conventional feed arm, the T-shaped slot T is completelyenclosed which is not the case in the present invention.

The key 10 is connected by conventional key con trolled power means,indicated by the character M, to a type bar actuating sublever 21. Themeans M includes a universal driving element or toothed rotary snatchroll 22 of known form for driving each of the type bars, not shown, ofthe typewriter. The sublever 21 is connected by link 23 to a type bar 24carrying the special type font 11. In the present invention only thetype bar 24 has been structurally modified so as to remove the portionillustrated by the broken lines and indicated by the letter A. Thisportion A which is part of each conventional type bar, not shown, in thetypewriter normally is arranged to engage the conventional escapementarch, not shown, to actuate the escapement system to effect stepwisemovement of the carriage. Thus, in this instance, when the type bar 24is caused to be actuated by depressing key 10, the type bar 24 is causedto rock inthe direction of the platen but does not contact theescapement arch thereby, avoiding actuation of the escapement system,with the result that the carriage remains stationary. The sub-lever 21is connected by means of a link 26 to the lug 19 on the feed arm 17. Itwill be apparent that rocking movement of sub-lever 21 will effectmovement of the feed arm in a corresponding direction thereby, rockingshaft 16 and effecting vertical upward movement of the ribbon vibrator12.

A conventional ribbon field control selector lever 27 is pivoted on theframe, as at 28, and has its lower end connected, as by link 29, to anarm 31 of a generally L-shaped lever 32 pivoted to the frame, as at 33.The other arm 34 of the lever 32 carries a laterally projecting pin 36which projects into an elongated slot 37 at the end of a lever 38adjacent lever 32 and operatively connected to the key controlled powermeans M. The lever 38 carries a laterally projecting pin 39 which isreceived in the slot T of the feed arm 17. It will be understood thatrocking of the selector lever 27 will effect movement of the lever 32about the axis of pivot 33 and by reason of the pin 36 in slot 37 willeffect corresponding movement of the end of lever 38. However, lever 38which is actuated by the instrumentalities of the key controlled powermeans M may move independently of lever 32. Pin 39 extends into the slotT of the feed arm 17 and rocking of the selector lever 27 will effectsliding movement of the pin 39 longitudinally within the longitudinalportion T of the slot T. Thus, as seen in FIGS. 3, 5 and 6, the pin 39will assume different posi-. tions within the slot T depending upon thedirection and degree of travel of the selector lever 27. When theselector lever 27 is moved to normal typing position, as seen in FIG. 5the pin 39 assumes a position within the slot portion T' which is mostremote from the axis of rock shaft 16. Accordingly, when lever 38 iscaused to be actuated, to the right, as viewed in FIG. 5, upon thedepression of one of the character printing keys, the pin 39 being inabutment with the right-hand edge of the slot portion T will cause thefeed arm 17 to rock counterclockwise, substantially to the positionillustrated by the broken lines thereby rocking shaft 16, acorresponding angle, also shown by the broken lines, and moving thevibrator 12 upwardly to a position where the inked field of the ribbon13 is impinged by a character font.

When the selector lever 27 is moved to the opposite position, asillustrated in FIG. 6, the pin 39 is caused to move to the position inthe slot portion T which is in closest proximity to the axis of shaft16. Thus, the same movement of lever 38, in the manner above described,will now effect a greater angular movement of the arm 14, substantiallyto the position illustrated by the broken lines in FIG. 6 to cause theribbon vibrator 12 to elevate the ribbon 13 so as to bring theobliterating por tion 13b into registration with a type font.

When the selector lever 27 is moved to the intermediate positionillustrated in FIG. 3, the pin 39 is aligned with the transverse portionT of the slot T so that when the lever 38 is caused to be actuated, thepin 39 will travel within the portion T clear of engagement with anyportion of the feed arm 17 so that the feed arm will remain stationaryand will not effect movement of the vibrator 12. This last describedcondition is utilized when it is desired to deactivate the ribbonvibrator, as when cutting a stencil. A spring 35 extending between theend of lever 32 and the lug 19 assists in retaining the parts inadjusted positions.

It will be understood that the selector lever 27 and associatedmechanism, just described, is generally conventional in structure andfunction and is described merely for the purpose of facilitating abetter understanding of the present invention which now will bedescribed in greater detail.

With the selector lever 27 in position for normal typing, as illustratedin FIG. 5, the pin 39 is disposed in registration with the cut-away 18of the feed arm 17. When key is depressed sublever 21 is caused to rockin a counterclockwise direction, as viewed in FIGS. 1 and 4, causinglink 26 to move to the right rocking the feed arm 17 counterclockwisewhich, in turn, rocks the shaft 16 and rocks the arm 14 upwardlysubstantially to the position shown by in FIG. 4. In such position, theribbon vibrator 12 is disposed in its uppermost position and the lowerribbon portion 13b now is in position so that it may be impinged upon bythe type font 11 to deposit obliterating pigment over a characterimprinted in error.

It will be noted that the provision of the cut-away 18 permits the feedarm 17 to move independently of and relative to lever 38. It will beunderstood that in normal operation, when the lever 38 is caused to beactuated upon depressing a character printing key, the lever 38 is drawnto the right, as viewed in each of the figures, and the pin 39 willengage the right-hand edge of slot portion T to effect rocking of thefeed arm 17 in a counterclockwise direction. Thus, the lever 38 and feedarm are caused to move simultaneously. However, in accordance with ourinvention, the feed arm 17 may move a greater angular distance so thatpin 39 actually is disposed outside of slot portion T, as shown in FIG.4.

The type font 11 includes a generally rectangular impinging surface ofsufficient area to cover the largest of the characters printed by thetypewriter. Preferably, the surface may include a plurality of minutebut closely spaced embossings of any suitable shape which when impingedon the lower ribbon portion 13b will efficiently transfer the opaquepigment over an imprinted error character and thereby obliterate thesame.

OPERATION The operation of the above-described embodiment of ourinvention briefly is as follows:

Assuming that a character has been imprinted in error, in order toeffect a correction, the conventional back-space key, not shown, isdepressed thereby. to

backspace the carriage, not shown, and locate the error character inposition to be operated upon by the obliterating font 11. Upondepression of the special key 10, the type bar 24 is caused toaccelerate towards the carriage to cause the type font 11 to impinge onribbon l3. Simultaneously, link 26 draws the feed arm 17 to the right,as viewed in FIG. 4, rocking the shaft l6 and arm 14 to elevate thelower ribbon portion 13b into position so that the type font 11 mayimpinge thereon and deposit opaque material over the error character toobliterate the same. It will be noted that the pin 39 is in registrationwith the cut-away 18 so that movement of the feed arm 17 is not impededby the pin. It will also be noted that the carriage has not moved, sincethe escapement system has not been actuated. Accordingly, the carriageremains in the same position for the next imprinting of a correctcharacter, according to conventional practice.

It will be understood that the preferred relationship of the parts foreffecting an error correction is when the selector lever 27 is adjustedfor normal typing as illustrated in FIG. 5 and, in such position ofadjustment, the pin 39 is disposed in registration with the cut-away 18so that maximum movement of the feed arm 17 and corresponding movementof the arm 14 may be achieved without interference from pin 39.

Various changes coming within the spirit of our in vention may suggestthemselves to those skilled in the art; hence, we do not wish to belimited to the specific embodiment shown and described or uses mentionedbut intend the same to be merely exemplary to the scope of our inventionbeing limitedvonly by the appended claims.

We claim:

1. In a power operated typewriter comprising character printingmechanism including printing control keys operatively connected to typebars, key controlled power means, paper support mechanism, spacing meansincluding an escapement arch operatively engageable by said type barsfor stepwise moving said paper support mechanism in a forward directionto accomplish printing a line of characters, a ribbon providing aprinting field and a print obliterating field, a ribbon vibrator, a feedarm operatively connected to said ribbon vibrator and actuated by theprinting control keys to guide said ribbon to bring a ribbonfieldmomentarily in impressing position, backspace drive means forstepwise moving said paper support mechanism in a backward direction inletter width increments, the improvement which comprises a manual keyoperatively connected to a special type bar carrying a universalobliterating type font, said type font being controlled by said manualkey to impinge on said ribbon, said special type bar being free of anyengagement 5 6 with said escapement arch whereby actuation of said anyof said printing control keys, said special type bar manual y will noteffect movement of Said P p p when actuated by said manual key movingsaid feed 3 f 'd g j q opegatwfely f lg arm and effecting elevation ofsaid ribbon vibrator to Sal ee arm 0 Sal We at or movmg position theprint obliterating field in impressing posifeed arm independently of anymovement effected by 5 the actuation of any of said printing controlkeys, said to be 'mpmged upon by Sald type font to Obmerme feed armhaving a slot permitting movement of the feed chal'acter imprinted inerrorarm beyond the movement effected by the actuation of

1. In a power operated typewriter comprising character printingmechanism including printing control keys operatively connected to typebars, key controlled power means, paper support mechanism, spacing meansincluding an escapement arch operatively engageable by said type barsfor stepwise moving said paper support mechanism in a forward directionto accomplish printing a line of characters, a ribbon providing aprinting field and a print obliterating field, a ribbon vibrator, a feedarm operatively connected to said ribbon vibrator and actuated by theprinting control keys to guide said ribbon to bring a ribbon fieldmomentarily in impressing position, backspace drive means for stepwisemoving said paper support mechanism in a backward direction in letterwidth increments, the improvement which comprises a manual keyoperatively connected to a special type bar carrying a universalobliterating type font, said type font being controlled by said manualkey to impinge on said ribbon, said special type bar being free of anyengagement with said escapement arch whereby actuation of said manualkey will not effect movement of said paper support mechanism, link meansoperatively connecting said feed arm to said special type bar for movingsaid feed arm independently of any movement effected by the actuation ofany of said printing control keys, said feed arm having a slotpermitting movement of the feed arm beyond the movement effected by theactuation of any of said printing control keys, said special type barwhen actuated by said manual key moving said feed arm and effectingelevation of said ribbon vibrator to position the print obliteratingfield in impressing position to be impinged upon by said type font toobliterate a character imprinted in error.